I have in the last few days noticed a minor problem involving my desktop wallpaper. (I use various photos, not the default images included by MX). Separate desktops' images are bleeding into each other: that is, the image that is the previously used desktop's wallpaper will remain on the new desktop I just switched to, and will be "stuck" behind the new desktop's image. If the previous desktop's image was larger, it will now look like the current desktop's image has simply been superimposed on the new one.

I upgraded to MX-17, which of course auto-upgraded to become MX-18, last week. I noticed this problem at I think the same time, although it could be a coincidence.

Hmmm...I unexpectedly solved my own problem, but I don't understand why it happened. After realizing that this is happening only on a certain desktop, I tried changing the "color" setting to see if anything would happen. It was set to "transparent," although I don't remember selecting that. I set it to "solid," and that immediately made the wrong desktop image disappear. So "transparent" is supposed to sort of make one desktop's image visible on another desktop? Why would I want that? It seems I accidentally used a desktop settings option I don't understand the point of. Mixing the wallpaper images.